42 ideas
21560 | Any linguistic expression may lack meaning when taken out of context [Russell] |
21561 | 'The number one is bald' or 'the number one is fond of cream cheese' are meaningless [Russell] |
10170 | While true-in-a-model seems relative, true-in-all-models seems not to be [Reck/Price] |
10166 | ZFC set theory has only 'pure' sets, without 'urelements' [Reck/Price] |
18130 | Axiom of Reducibility: there is always a function of the lowest possible order in a given level [Russell, by Bostock] |
10175 | Three types of variable in second-order logic, for objects, functions, and predicates/sets [Reck/Price] |
10165 | 'Analysis' is the theory of the real numbers [Reck/Price] |
10174 | Mereological arithmetic needs infinite objects, and function definitions [Reck/Price] |
10164 | Peano Arithmetic can have three second-order axioms, plus '1' and 'successor' [Reck/Price] |
10172 | Set-theory gives a unified and an explicit basis for mathematics [Reck/Price] |
10167 | Structuralism emerged from abstract algebra, axioms, and set theory and its structures [Reck/Price] |
10169 | Relativist Structuralism just stipulates one successful model as its arithmetic [Reck/Price] |
10179 | There are 'particular' structures, and 'universal' structures (what the former have in common) [Reck/Price] |
10181 | Pattern Structuralism studies what isomorphic arithmetic models have in common [Reck/Price] |
10182 | There are Formalist, Relativist, Universalist and Pattern structuralism [Reck/Price] |
10168 | Formalist Structuralism says the ontology is vacuous, or formal, or inference relations [Reck/Price] |
10178 | Maybe we should talk of an infinity of 'possible' objects, to avoid arithmetic being vacuous [Reck/Price] |
10176 | Universalist Structuralism is based on generalised if-then claims, not one particular model [Reck/Price] |
10177 | Universalist Structuralism eliminates the base element, as a variable, which is then quantified out [Reck/Price] |
10171 | The existence of an infinite set is assumed by Relativist Structuralism [Reck/Price] |
21562 | There is no complexity without relations, so no propositions, and no truth [Russell] |
10173 | A nominalist might avoid abstract objects by just appealing to mereological sums [Reck/Price] |
21181 | Relativity and Quantum theory give very different accounts of forces [Hesketh] |
21183 | Thermodynamics introduced work and entropy, to understand steam engine efficiency [Hesketh] |
21191 | Photons are B and W° bosons, linked by the Higgs mechanism [Hesketh] |
21199 | Spinning electric charge produces magnetism, so all fermions are magnets [Hesketh] |
21180 | Electrons are fundamental and are not made of anything; they are properties without size [Hesketh] |
21189 | Electrons may have smaller components, bound by a new force [Hesketh] |
21182 | Quantum mechanics is our only theory, and is very precise, and repeatedly confirmed [Hesketh] |
21184 | Physics was rewritten to explain stable electron orbits [Hesketh] |
21187 | Virtual particles can't be measured, and can ignore the laws of physics [Hesketh] |
21185 | Colour charge is positive or negative, and also has red, green or blue direction [Hesketh] |
21194 | The Standard Model omits gravity, because there are no particles involved [Hesketh] |
21195 | In Supersymmetry the Standard Model simplifies at high energies [Hesketh] |
21197 | Standard Model forces are one- two- and three-dimensional [Hesketh] |
21188 | Quarks and leptons have a weak charge, for the weak force [Hesketh] |
21186 | Quarks rush wildly around in protons, restrained by the gluons [Hesketh] |
21192 | Neutrinos only interact with the weak force, but decays produce them in huge numbers [Hesketh] |
21196 | To combine the forces, they must all be the same strength at some point [Hesketh] |
21190 | 'Space' in physics just means location [Hesketh] |
21193 | The universe is 68% dark energy, 27% dark matter, 5% regular matter [Hesketh] |
21198 | If a cosmic theory relies a great deal on fine-tuning basic values, it is probably wrong [Hesketh] |